Effects of ambient oxygen concentration on the radiative and pollutant emission characteristics of laminar natural gas jet flames

摘要

An experimental study of temperature profiles, composition profiles, radiative characteristics, and emission indices of carbon monoxide and nitrogen oxides, in laminar natural gas diffusion flames at jet exit Reynolds numbers less than 1850 and burning in an oxygen-enriched concentric air stream is presente.d A scanning infrared camera was used to measure the brightness temperature and a fine-wire thermocouple was used to measure the gas temperature in the flames. A pyrheliometer was used to measure the total radiation flux. Results show that the radiative fraction of heat release increases, the emission indices of nitrogen oxides increase, and the emission index of carbon monoxide decreases with oxygen-enrichment of the co-flow stream.